Im about to start now. At this point, I suspect a simple typo in one of the dest[iloop+1][eloop+1] = ((source[iloop-1+1][eloop+1]+...... lines is zeroing out every second vertex value in either array 1 or array 2.
"There is no fate but what WE make." - CEO Cyberdyne Systems Corp. A8.30.5 Commercial